package com.ymatou.apigateway.parameter;

import java.security.Key;
import java.security.MessageDigest;
import java.security.Security;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class AesUtil {

	private static Cipher encryptCipher = null;

	private static Cipher decryptCipher = null;

	private static final String IV_128 = "iv_openapi_ymt_q";
	private static final String KEY_128 = "^openapi@ymt.cn$";

	static {

		try {
			Security.addProvider(new com.sun.crypto.provider.SunJCE());

			SecretKeySpec secretKey = new SecretKeySpec(IV_128.getBytes(),
					"AES");
			IvParameterSpec param = new IvParameterSpec(KEY_128.getBytes());
			// Cipher对象实际完成加密操作
			encryptCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			encryptCipher.init(Cipher.ENCRYPT_MODE, secretKey, param);

			decryptCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
			decryptCipher.init(Cipher.DECRYPT_MODE, secretKey, param);

		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 将byte数组转换为表示16进制值的字符串， 如：byte[]{8,18}转换为：0813， 和public static byte[]
	 * hexStr2ByteArr(String strIn) 互为可逆的转换过程
	 * param arrB 需要转换的byte数组 return 转换后的字符串 throws Exception
	 * 本方法不处理任何异常，所有异常全部抛出
	 */
	public static String byteArr2HexStr(byte[] arrB) throws Exception {

		int iLen = arrB.length;
		// 每个byte用两个字符才能表示，所以字符串的长度是数组长度的两倍
		StringBuffer sb = new StringBuffer(iLen * 2);
		for (int i = 0; i < iLen; i++) {
			int intTmp = arrB[i];
			// 把负数转换为正数
			while (intTmp < 0) {
				intTmp = intTmp + 256;
			}

			// 小于0F的数需要在前面补0
			if (intTmp < 16) {
				sb.append("0");
			}

			sb.append(Integer.toString(intTmp, 16));
		}

		return sb.toString();
	}

	/**
	 * 将表示16进制值的字符串转换为byte数组， 和public static String byteArr2HexStr(byte[] arrB)
	 * <p/>
	 * 互为可逆的转换过程
	 * <p/>
	 * <p/>
	 * <p/>
	 * param strIn 需要转换的字符串 return 转换后的byte数组 throws Exception
	 * <p/>
	 * 本方法不处理任何异常，所有异常全部抛出
	 */
	public static byte[] hexStr2ByteArr(String strIn) throws Exception {

		byte[] arrB = strIn.getBytes();

		int iLen = arrB.length;

		// 两个字符表示一个字节，所以字节数组长度是字符串长度除以2
		byte[] arrOut = new byte[iLen / 2];

		for (int i = 0; i < iLen; i = i + 2) {
			String strTmp = new String(arrB, i, 2);
			arrOut[i / 2] = (byte) Integer.parseInt(strTmp, 16);
		}

		return arrOut;
	}

	/**
	 * 加密字节数组
	 * <p/>
	 * <p/>
	 * <p/>
	 * param arrB 需加密的字节数组 return 加密后的字节数组 throws Exception
	 */
	public static byte[] encrypt(byte[] arrB) throws Exception {
		return encryptCipher.doFinal(arrB);
	}

	/**
	 * 加密字符串
	 * <p/>
	 * <p/>
	 * <p/>
	 * param strIn 需加密的字符串 return 加密后的字符串 throws Exception
	 */
	public static String encrypt(String strIn) throws Exception {
		return byteArr2HexStr(encrypt(strIn.getBytes())).toUpperCase();
	}

	/**
	 * 解密字节数组
	 * <p/>
	 * <p/>
	 * <p/>
	 * param arrB 需解密的字节数组 return 解密后的字节数组 throws Exception
	 */
	public static byte[] decrypt(byte[] arrB) throws Exception {
		return decryptCipher.doFinal(arrB);
	}

	/**
	 * 解密字符串
	 * <p/>
	 * <p/>
	 * <p/>
	 * param strIn 需解密的字符串 return 解密后的字符串 throws Exception
	 */
	public static String decrypt(String strIn) throws Exception {

		return new String(decrypt(hexStr2ByteArr(strIn)));

	}

	/**
	 * 从指定字符串生成密钥，密钥所需的字节数组长度为8位 不足8位时后面补0，超出8位只取前8位
	 * <p/>
	 * <p/>
	 * <p/>
	 * param arrBTmp 构成该字符串的字节数组 return 生成的密钥 throws java.lang.Exception
	 */
	private Key getKey(byte[] arrBTmp) throws Exception {

		// 创建一个空的8位字节数组（默认值为0）
		byte[] arrB = new byte[8];

		// 将原始字节数组转换为8位
		for (int i = 0; i < arrBTmp.length && i < arrB.length; i++) {
			arrB[i] = arrBTmp[i];
		}

		// 生成密钥
		Key key = new SecretKeySpec(arrB, "DES");

		return key;
	}

	public static void main(String[] args) {
		try {
			System.out.println(getMd5("dfasdsfg"));
			//            System.out.println(encrypt("123456"));
			//            System.out.println(decrypt(encrypt("123456")));
			//            System.out.println(decrypt("F8CF4E9AE8690417A25E3E16B107A8B6524170E8AD939154AFED08BD72D3456DDDD8B81077271D86ABCBF7C21836F7F3C3C648EEE5D1F4BD773227944B57D402AD6A650003A387F708BA572BDCDF490736E35768E6764651D16ADC31758AA43FA135DF4B79646E4C7BD41FC02BA286442AB7EAF19C9FFAB07FE92D7011686773C4DDACBAB9E5BD8236BD6B31C98AEF25B21B6A706CBF14C2958A22B6C2F6FCFCCAAE6C63D5EE045C45F7EC1751ED0271B231F3449C8C6CAC46E0A5400E497BCC44E3ABAEBEA4EFEB787EAC9C941FD74B"));
		} catch (Exception e) {
		}
	}

	/**
	 * 解密字节数组
	 * <p/>
	 * <p/>
	 * <p/>
	 * param arrB 需解密的字节数组 return 解密后的字节数组 throws Exception
	 */
	public static String encryptTradingPwd(String pwd) throws Exception {
		return getMd5(encrypt(encrypt(encrypt(pwd))));
	}

	public static String getMd5(String text) {
		try {
			char[] hexDigits = {'0', '1', '2', '3', '4', '5', '6', '7', '8',
					'9', 'A', 'B', 'C', 'D', 'E', 'F'};
			MessageDigest md = MessageDigest.getInstance("md5");
			md.update(text.getBytes("UTF-8"));

			byte[] bytes = md.digest();
			int j = bytes.length;
			char[] c = new char[j * 2];
			int k = 0;

			for (int i = 0; i < j; i++) {
				byte b = bytes[i];
				c[k++] = hexDigits[b >>> 4 & 0xf];
				c[k++] = hexDigits[b & 0xf];
			}

			return new String(c);
		} catch (Exception ex) {
			throw new IllegalStateException(ex);
		}
	}
}
